Guide



July 30, 1935. w. H. RADFORD GUIDE Filed Feb. 10, 1950 INVEA/TOR. MOW/0m hfPadfin/"d m W; ZZZ/M ATTORNEYS.

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Leandro, cuia; assignor to Caterpillar Tractor 00., San Leandro, Calif., a corporation of California Application February 10, 1930,- Serial No. 427,391 11 Claims; ('01. 74-41:)

My invention relates to power transmission machinery, particularly to control mechanism adapted to occupy a plurality of control positions, and is especially related to a constraining or confining means for the clutch shifting mechanism of such transmissions.

In certain types of tractors it is customary to steer or guide the tractor by means of a variable division of power between the driving means for the vehicle. In order that the power may be regulated to steer the vehicle as desired. there is ordinarily provided a manually controllable means for adjusting the division of power. Such manual controls are subjected to extraordinarily severe service. Not only are the manual controls on a tractor strenuously used but they are often grossly abused as well. As they are usually situated on a tractor they furnish convenient hand grips to aid the tractor operator in mounting and dismounting from the machine, thus introducin material lateral stresses.

It is therefore an object of my invention to provide a mounting or guide for the control levers of a vehicle such as a tractor.

Another object of my invention is to provide a mounting for the control levers which in an improved manner renders them durable and serviceable.

The foregoing and other objects are attained in the embodiment of the invention shown in the drawing, in which Fig. 1 is a cross section on a transverse vertical plane of a transmission housing of a tractor showing the guide of my invention installed therein.

Fig. 2 is a side elevation of a transmission housing disclosing the guide of my invention installed therein, portions of the transmission housing being cut away on a vertical longitudinal plane to disclose the interior construction.

Fig. 3 is a detail showing in plan the guide of my invention, portions of the transmission casing being disclosed in section on the line 3-3 of Fig. 2.

In its preferred form, the guide of my invention comprises a pair of parallel lugs forming a guide way and generally includes a pair of nested members fastened to a transmission housing for confining to planar movement an extension on one end of a ball-mounted lever.

While I have chosen to describe my invention as it is embodied in a tractor and particularly in connection with the transmission mechanism thereof, the invention is applicable to a number of environments. In a usual tractor installation,

however, there is provided a transmission housing I, ordinarily of cast metal, on which are mounted one or more control levers, such as I and I, arranged for convenient operation by the driver of the tractor. Since these levers and 5 their associated parts are substantially identical 9. description of but one of them will suffice.

Each lever preferably includes a grip l mounted at one extremity of a shank ii which, intermediate its ends, is enlarged to provide a spher- 1o ical portion or ball i2 confined between suitably formed plates II secured to the upper face of the transmission housing 0. A guard plate ii is customarily provided over the plates it to prevent the egress of on from the transmission casu ing and the ingress of dirt thereto. Depending from the ball I! is an extension ll of the lever which is pierced by an aperture to form a journal for a pin i1 securing a clevis it to the extension.

The clevis is part of a linkage for controlling a steering clutch, not shown, of the tractor and is extended by a threaded shank ii passing through an enlarged aperture in one leg of a bell crank 2i pivoted, as. at 22. to the transmisas sion housing. An adjusting nut it maintains the relationship of the leg 2| and the shank il against the urgency of a spring 24. The bell crank is made with a second leg 26 adapted to move between two extreme positions one of which so is established by a stud 21 piercing the transmission housing. The leg 28 is adapted to abut against an adjusting screw 28 which is clamped in adjusted position in a split sleeve 20 formed at the upper end of a control yoke I i The lower 86 end of the control yoke is provided with a spherical bushing 32 confined in a cylindrically bored plug 33 pressed into the transmission housing, while between the ends of the yoke is provided an annulus 14 having removable studs 36 and 40 ll projecting radially thereinto from diametrally opposite points. The studs II and 31 are adapted to engage a steering or clutch mechanism in the customary fashion.

By virtue of the linkage described, movement of the lever B is efiective to translate the studs 38 and 31 in substantiallya horizontal transverse plane'to actuate the associated steering mechanism, not shown. Since the lever I is connected through a similar train of linkage, its movement 60 is also effective to translate substantially in a horizontal transverse plane the corresponding studs connected therewith.

In order toassist in confining the levers I and 8 to movement in a single plane and in order to strengthen them for resistance against lateral displacement, I provide a suitable guide for the lower extremities ll thereof. The lower portion of the extension II is preferably flattened, as particularly indicated in Fla. 3, to be received in a guide way ll boundedby a pair of lugs ll and 43 which are conveniently formed by the upturned extremities of a pair of nested members 44 and ll such as the channels disclosed in the drawing. These nested channels-are preferably held in place by studs 41 received in bosses ll formed in the transmission housing. Although the nested channels are the preferred construction and serve admirably to confine to planar motion the lower extensions on both the levers 1 and 8, nevertheless comparable guide 11188 can be separately and individually fabricated, if desired, or the upstanding lugs can be formed integrally with the transmission housing 8 itself.

By virtue of the construction of my invention, there are provided guides for the operating levers l and 8 which confine them to planar movement and which are extremely simple and rugged. The guides withstand easily the side thrust on the levers and adequately resist such side thrust even though it is applied at a considerable distance from the fulcrum of the lever so that they can be relatively light in weight but ample in strength. Furthermore, because of the provision of the lever constraining guide for each operating lever, the universal lever mounting comprising ball If and plates is can be effectively employed; the type of mounting being extremely desirable because it, especially in conjunction with the guard plate it, provides an economical and effective seal between the lever and the casing into which the lever extends.

It is to be understood that I do not limit myself to the form of the guide shown and described herein, as the invention, as set forth in the fol-. lowing claims may be embodied in a plurality of forms.

I claim:

1. In a guide, a transmission housing, a pair of levers, flattened extensions on said levers, ball mountings for securing said levers to said housing, and a pair of nested channels fastened to said housing to provide guides constraining each of said extensions to movement in one plane.

2. In a guide, a transmission housing, ball mounted shift levers on said housing, and a pair of nested channels fastened to said housing, said channels engaging said levers for constraining said levers to sliding movement relative to said housing.

3. In a guide, a housinghlevers mounted to pivot with respect to said housing, an extension on each of said levers, and a pair of nested members fastened to said housing and forming a pair of spaced guideways, in which said extensions engage for confining each of said levers to movement in one plane.

4. In a guide, a housing, a pair of U-shaped members nested to provide a pair of parallel guideways, means for fastening said members to said housing, a pair of ball mounted shift levers on said housing, and extensions on said levers adapted to slide in said guide ways.

5. The combination with a shift lever having a pivot of an element connected to said lever and adapted to be shiftedby said lever, and a guide for said lever comprising a pair of fixed nested channels.

6. The combination with a shift lever having a pivot with a fixed nested channel guide for one end of said lever, and an element connected to said lever intermediate said pivot and said nested 1channel guide, and adapted to be shifted 'by said ever.

7. In a guide, a pair of levers, flattened extensions on said levers, mountings for pivoting said levers, and a pair of nested channels of different widths fastened with said flattened extensions swinging between faces of said nested channels.

8. The combination with a plurality of shift levers, each lever having a pivot and an element connected to said lever and adapted to be shifted by said lever, and a guide for said levers formed of a pair of nested channels.

9. The combination with a plurality of shift levers, each lever having a pivot and an element connected to said lever and adapted to be shifted by said lever, and-a guide for said levers formed of a pair of U-shaped members nested to provide a pair of parallel guideways.

10. The combination with a plurality of shift levers, each lever having a pivot and an element connected to said lever and adapted to be shifted by said lever, and a guide for said levers formed of a pair of nested channels of different widths positioned to provide a plurality of guideways for said levers.

ll. In a guide, a pair of levers, elements rigid with said levers, mountings for pivoting said levers, and a pair of nested channels of different widths fastened to provide a pair of guideways formed by faces of said nested channels, the elements being slidable in said guideways.

WILLIAM H. RADFORD. 

